LABS was conceived to address important issues in bariatric surgery and metabolism in adults, exploring relationships of patient characteristics, clinical conditions, serologic and genetic markers, and clinical, psychosocial and health economic outcomes. The primary achievements of LABS have been establishing a research consortium and its infrastructure;defining domains of exploration, specific research questions and an effective study design to efficiently address those questions;identifying appropriate metrics;designing and implementing a web-based data collection system and an extensive database;completing a cohort of over 5000 participants to study the short-term safety of bariatric surgery;enrolling approximately 2000 participants into a 2400 person cohort intended to address longer term safety and efficacy;and implementing 2 substudies. The Data Coordinating Center (DCC) provides logistical and administrative support and expertise in database management, website construction and maintenance, computer systems, epidemiology, biostatistics, and methodology. During this proposed continuation of LABS, the DCC will continue to support the consortium in all aspects of study design, conduct, analysis, logistics, and administration. This includes maintaining the distributed data entry and database management systems;maintaining contact with the NIDDK-supported biospecimen and data repositories;administering a subcontract with a Central Laboratory if necessary;assisting the study pathologist with respect to biopsy specimen tracking and data collection; maintaining and improving the study website that has public, private, participant and systems areas; providing logistical support to the Clinical Centers, NIDDK Project Scientist, committees and subcommittees, central facilities, and Data and Safety Monitoring Board (DSMB);and analyzing and reporting study results to better inform the research and public communities regarding long-term outcomes following bariatric surgery. RELEVANCE (See instructions): Obesity is a major public health problem expected to increase in the future. Bariatric surgery is currently the most effective long term therapy. This multi-center consortium was created to "faciliatate coordinated clinical, epidemiological, and beahvioral research in...bariatric surgery". The data coordinating center provides logistical and scientific support, and developed the core database.